Robotic versus laparoscopic splenectomy: a systematic review of perioperative outcomes

Elective splenectomy has many indications and can be performed via an open approach or in a minimally invasive manner [1]. Since the inception of laparoscopic splenectomy (LS) [2], improvements of laparoscopic tools for ligation over time have popularised the approach [3]. However, LS does have its limitations, such as a steep learning curve [4]. Multiple studies have reported that in difficult operational circumstances such as splenomegaly, obesity, haematological malignancies and previous laparotomies, LS is associated with increased morbidity and conversion rates to open surgery [5‐8].

With the introduction and increasing availability of the surgical robot in the operative arena [9, 10], general surgeons are adopting the robotic platform to benefit from its markedly advanced endowristed instruments [11]. While both laparoscopic and robotic surgery are classed as minimally invasive techniques, there are studies which appear to suggest superiority of robotic splenectomy (RS) over the laparoscopic approach [12, 13].

As such, we conducted a systematic review to determine whether RS has greater positive perioperative outcomes in comparison to LS in the adult population.

There were 47 potential studies that satisfied the inclusion criteria in the initial search (Fig. 1). Of these, we excluded 44 articles with reasoning as follows: 14 due to incorrect study design; 12 were conference abstracts; 8 studies used the wrong comparator; 2 studies were video presentations; 2 studies were in the wrong setting; 5 studies consisted of a paediatric population and 1 study used the wrong intervention. For the final systematic review, we included three studies involving a total of 72 patients (28 in the RS group, 44 in the LS group) published between and inclusive of 2005 and 2018.

The characteristics of the three studies are further listed in Table 1. Two of the three studies are RCTs [14, 16]. The remaining article is a case–control study [15]. All three studies involved conducting a splenectomy. Data obtained from all three included studies are listed in Table 2 and detailed below.

This study highlighted RS to have reduced blood loss in comparison to LS [15, 16]. In particularly difficult cases involving malignant hemopathies, splenic tumours, partial splenectomy and splenectomy in liver cirrhosis, the RS approach may prove to be potent for decreasing the risk of haemorrhagic complications during surgery and performing minimally invasive splenectomy where the LS approach has proven to be very difficult [17].

The RS approach was reported to have no patient cases converting to open surgery and no postoperative complications or mortality in comparison to LS. In addition to these findings, breakdown of the postoperative complications revealed that a larger proportion of postoperative LS complications were classed as grade IV [14, 16]. These findings are largely consistent with a recent meta-analysis comparing RS and LS in the surgical management of non-traumatic diseases of the spleen. The study showed RS to have both significantly lower conversion rates to open surgery and postoperative complications in comparison to LS. Perioperative mortality was not observed in the RS group [18].

We found no significant difference in LOS in the three studies that were compared. One study based in Austria [15] attributed similar and relatively longer LOS for both RS and LS due to less pressure from insurance companies in comparison to the United States. In this regard, previous research of the US healthcare system has elucidated nonclinical factors such as race, education, gender and socioeconomic status to be associated with patients being uninsured and experiencing a longer LOS [19]. We can provide two counter arguments validating shorter LOS. The first is that a prolonged LOS has the potential to deny healthcare access to critically ill patients to timely access to treatment. The second is that patients with prolonged LOS are also at a higher risk of developing nosocomial infections and subsequent unplanned hospital readmissions, which, in turn, disadvantages both patients and hospitals alike [20, 21].

Another important issue raised when comparing RS and LS modalities is cost analysis. Our findings indicated that there was no significant procedural cost difference between the two approaches [15, 16]. It is important to consider that in the two studies that reported this parameter, the currencies used to calculate the total costs for the procedures were not the same, making it difficult to comparatively analyse the cost benefits of both RS and LS. In addition to this, there are currently only two studies comparing the costs in US dollars between RS and LS, which involve both adult and paediatric populations. Both studies concluded that while RS is more expensive than LS, it is feasible [22, 23].

Our study found RS to have an increased operative time in comparison to LS. It is likely that the published series on RS are from the early adopters of robotic surgery, hence the longer operating times. Setting up and docking the robot adds time to the procedure. Finally, most robotic surgeons would agree that due to the 3D-HD × 10 magnified view, they see more unnamed blood vessels and to secure these with clips requires frequent instrument exchanges which adds time to the surgery. Hopefully, with the introduction of advanced energy devices (e.g., SynchroSeal® Intuitive Surgical), operating times will improve.

A retrospective cohort study by Giza et al. compared RS and LS approaches and was conducted over a span of 17 years [24]. In this study, patients were assigned via a scoring system to one of two groups—simple or complex, according to the degree of surgical complexity. The researchers found that for complex, difficult splenectomies, the robotic system was significantly beneficial. Further studies that stratify splenectomy procedures according to surgical complexity will enhance our understanding of the role of RS in complex procedures.

Our study is significant in that it evaluates the perioperative parameters involved in both RS and LS. However, there are a few limitations to our findings. First, many articles were excluded from our systemic search because they focussed on surgeries other than minimally invasive splenectomies. Second, there was heterogeneity in our results due to the limited number of articles that were analysed that satisfied our inclusion criteria. Third, due to the limited adult patient volume analysed in this study, the power of our findings is relatively low. Fourth, this study could not analyse the long-term outcomes of both RS and LS due to lack of data. We must also mention the possibility of selection bias in the robotic group, as in most cases this was a novel procedure.

In conclusion, our systematic review has shown that RS was associated with lower blood loss, a lower risk of conversion to open surgery and fewer postoperative complications. However, there was no significant difference between RS and LS in terms of LOS and cost benefit. Lastly, RS had a higher intraoperative time in comparison to LS. While these findings are encouraging in favour of RS, it is important to emphasise that further larger-scale comparison studies are required to be conclusive.